Research On Measuring And Evaluation Technology Of Partial Discharge Detector

With the rapid expansion of the scale of China's power grid construction,the safety and reliability of power system operation have also met higher standards.The partial discharge generated in the normal operation of the power grid is one of the causes of the internal insulation damage of the power equipment,and it is also an important indicator of the damage of the insulation of the power equipment.Therefore,partial discharge detection of power equipment can effectively find the hidden danger of the existence of insulation material as early as possible,judge the degree of insulation damage and avoid sudden insulation accidents,which is of great significance to the safe operation of the power grid.Off-line,on-line and live monitoring of partial discharge equipment has become an important means to ensure the safe operation of equipment.A variety of different types of partial discharge detectors are generated based on partial discharge characteristics.However,due to the uneven performance levels of partial discharge detection equipment produced by different companies,there are many faults and defects.In order to avoid potential hidden dangers to the main power equipment due to partial discharge,it is necessary to evaluate the equipment for detecting partial discharge.This paper takes the function detection of partial discharge detector of power equipment as the main line.The main work includes the introduction of partial discharge type detection and the evaluation of partial discharge instrument.The partial discharge detection part expounds the partial discharge theory comprehensively,and introduces the detection principle,method and common detection equipment of pulse current method,Ultra High Frequency method,ultrasonic method and transient ground voltage method;The evaluation part of the Partial Discharge is a detailed introduction to the evaluation principle and method of the Ultra High Frequency method,the ultrasonic method and the transient ground-to-ground voltage method,and establishes a relatively complete evaluation system for the Partial Discharge.The circuit includes a circuit for designing a ps-level controllable pulse signal generator and a database for a GIS internal PD type;And the analysis results of three mainstream Partial Discharge instruments and the on-site GIS Ultra High Frequency online detection system were analyzed.